//1.数学运算
let a = 1 + 2;
let b = 2 - 1;
let c = 2 * 3;
let d = 4 / 2;
let e = 5 % 2;
let f = 2 ** 3;
console.log(a, b, c, d, e, f);

//2.逻辑运算
let a1 = true && false;
let b1 = true || false;
let c1 = !true;
console.log(a1, b1, c1);

//3.关系运算
let a2 = 1 < 2;
let b2 = 1 > 2;
let c2 = 1 <= 2;
let d2 = 1 >= 2;
let e2 = 1 == 2;
let f2 = 1 != 2;
console.log(a2, b2, c2, d2, e2, f2);

/**
 * var let const的解释
 * var: 函数作用域
 * let: 块作用域
 * const: 块作用域，常量
 */
